Ipod playback truncated at around 20-22 mins

[scrofula 101]

Having problems with get_iplayer in Linux Mint 16 for a while now. Using
current version 2.86. All the radio files I obtain playback fine on the
computer but when I transfer them to ipod nano using itunes on Windows
8.1 they cut out at around 20-22 mins and it skips to the next track.
Shorter files are fine. Podcasts are fine. Using Windows version of
get_iplayer to fetch new copies of the files to the Windows partition
results in no problems with playback in full. No error messages in
Linux. I use itunes as I prefer it for getting the track order of files
the right way. File system on Linux is ext3.

Very puzzled by this. Any suggestions?

Thanks